Images

Developing pallid sturgeon embryo.

Biologists at Columbia Environmental Research Center drawdown and seine a pond to collect reproductive pallid sturgeon.  The pond has been specially designed to provide turbid, flowing water that pallid sturgeon need to thrive.

Hoffstadt Creek is one of the salmon release sights after being radio tagged. This picture is taken just downstream from the release sight after a fish release.

These juvenile bighead carps are used to find potential physical, biological or chemical controls as part of an integrated pest management approach for natural resource managers.

Asian carp are invasive species that could pose substantial environmental risks and economic impacts if they become established.

These juvenile silver carps are used to find potential physical, biological or chemical controls as part of an integrated pest management approach for natural resource managers.

Asian carp are invasive species that could pose substantial environmental risks and economic impacts if they become established.

A close-up image of lignite-dominated gravel sampled from a spawning area with Petite Ponar sampler.

Collecting and storing substrate samples using a Petite Ponar sampler (top right) for later analysis. 

A USGS scientist operates a Petite Ponar substrate sampler to sample bed material in an area identified as a pallid sturgeon spawning location on the Yellowstone River, North Dakota.

USGS research vessel outfitted with a compact multibeam sonar echosounder system with an inertial motion unit and real time kinematic positioning global positioning system (RTK GPS) surveys the Yellowstone River near Fairview, North Dakota.

Pallid sturgeon eggs become adhesive minutes after fertilization.  Scientists are working to understand the factors that influence the adhesiveness of sturgeon eggs.

Scientist surgically implants an acoustic transmitter in a shovelnose sturgeon to monitor spawning behavior during controlled experiments.

Acoustic telemetry transmitter used to monitor shovelnose sturgeon and pallid sturgeon during spawning in specially constructed ponds at the Columbia Environmental Research Center.

Researchers count out 800 eight-day old, free embryo lake sturgeon for studies of downstream dispersal in experimental streams.

USGS Biologist prepares to artificially spawn a female lake sturgeon in the laboratory at the Columbia Environmental Research Center. 

A USGS scientist uses a remotely controlled "z-boat" to survey the experimental ponds at the Columbia Environmental Research Center.

Researchers prepare to release pallid sturgeon code 39 following a post-spawn analysis to confirm a successful release of eggs during the spawning event.

Female pallid sturgeon captured in the Missouri River near Boonville, MO. 

Vegetation grows on an east-facing cliff along Bull Run near Sudley Springs in Manassas National Battlefield Park, Virginia. The cliffs are islands of specialized habitat; they support plant species found nowhere else in the park, including locally uncommon or rare species.

East-facing cliff approximately 30 meters downstream from Farm Ford along Bull Run in Manassas National Battlefield Park, Virginia.

A USGS research vessel uses DIDSON sonar imaging on the Yellowstone River to document pallid sturgeon spawning activities on June 27, 2014.

Ten minute samples from ichthyoplankton nets deployed near the bottom of the Missouri River.  Samples are sorted and searched for paddlefish and sturgeon free embryos.